The False Division of Tropical & Sidereal Astrology
In the first post in this series, The False Division of Tropical Vs. Sidereal Astrology, Pt. 1, we discussed the misconceptions that lead to the notion that the main difference between tropical and sidereal astrology is cultural (ie., the notion that Western astrology is “naturally” tropical, and only Vedic or Indian astrology uses sidereal time). We recommend starting with that post and checking out Pt. 2 for digging into the history of Babylonian astrology and its influence on the West, which also helps disprove the assumption that “it’s only cultural.”
In this post, we will look at another concept that makes Westerners resistant to looking at the insights and value of sidereal astrology – the notion that tropical astrology is “seasonal” and sidereal astrology is “zodiacal.” The problem here is that the seasons actually exist in both systems, and the seasons are different depending on where you are on the globe.
As Kenneth Bowser, the leading modern authority on Western sidereal astrology says, “If you ignore either the equatorial OR ecliptic system, you ignore half the chart” (1). The truth is that no astrologer should ever be looking only to the zodiac or the earth’s rotations. The Earth is rotating while the Sun revolves. Any astrologer worth their salt will be looking at both of these paths of motion in concert to one another; you need both an understanding of the rotation of the Earth (the equinoxes and solstices) and the revolutions of the Sun along the ecliptic. This is true of either a sidereal or tropical astrologer – everyone, regardless of zodiac system, should be looking at the chart in three dimensions.
Have a look at the following illustration of the ecliptic and celestial poles. See how the north ecliptic pole is fixed while the celestial pole reflects the earth’s axial tilt, or obliquity.
The 23.4-23.6° difference between these two poles is also the number of degrees difference between your chart in tropical and sidereal astrology! It is also a real, observable, measurable, widely agreed-upon astronomical difference.
Now have a look at that same Earth-Sun relationship in the context of the zodiac, the band of stars along the ecliptic:
Again, as emphasized strenuously is Part 2, the spring equinox is observably in Pisces – and if it were not so, we would not be on our way into the “Age of Aquarius.” But again, tropical astrologers hew strongly to the notion of there being a seasonality to certain signs. Itcan be easy to walk away from many corners of the astrological interwebs with the impression that there are somehow two different “versions” of the equinox – the one that is subject to precession and has moved into Pisces (sidereal), and the one that has somehow stayed fixed at the cardinal points since ancient times and remains in Aries (tropical). As if there is an alternate version of the vernal equinox somewhere in the sky where the equinox passes reliably through 0° Aries every spring, but it is only visible through Western tropical glasses. But there simply isn’t. There is just one spring equinox and it moves very slowly through one sign at a time. As Bowser notes in his article on Cyril Fagan (who established the Fagan-Bradley ayanamsa for Western sidereal chart calculation):
“The Sun rises in the constellation Pisces at the Northern Hemisphere Vernal Equinox actually, not symbolically.” (2).
You might even encounter tropical astrologers saying that the Tropic of Cancer and Tropic of Capricorn are so named because of an astronomically consistent association of these points with the cardinal signs. But even those points have also moved, even if their names have not. NASA continues to use those names (Tropic of Cancer, Tropic of Capricorn) only because they are familiar carryovers from ancient times – when the Sun was in the constellations of Cancer during the June solstice, and Capricorn during the Winter solstice, respectively (4). But now, the Tropic of Capricorn is currently at 23.5° Virgo; the Tropic of Cancer is at 23.5° Pisces. NASA, as you should probably know, has little interest in astrology, and uses classical and mythological (and sometimes entirely made-up!) names for space objects and astronomical points. In other words, the names NASA uses for stuff in space have nothing to do with astrology and should not be used to substantiate the naming practices of any astrological system.
All of that is to say, tropical astrology is obviously not practiced by astronomers – and sometimes, it isn’t even really practiced by trained “tropical” astrologers. This has been a problem since the Catholic church outlawed astrology in the Middle Ages and continues today (especially on TikTok…). It creates a situation where, ironically, many “tropical” astrologers are using only the symbolic zodiac – while practicing a system that relies more heavily on seasonality to work. And thus, pop astrology stereotypes about star sign compatibility dominate everyone’s understanding of astrology and deter those who might appreciate astrology’s deeper insights, which only come from a more dynamic, three-dimensional view of the chart. This is especially true in terms of the IC/MC axis and the ASC/DSC axis – those points are some of the most sensitive in the chart, and anyone who looks at a natal chart and immediately zones in on the Sun sign without regard for the major axes is missing, like, the whole bag.
Even though some Western tropical astrologers might admit their zodiac signs “have nothing to do with” the constellations, obviously, the signs did originally have to have at least something to do with the sky. After all, the names, archetypal lore, and characteristics of each of these signs are all deeply connected to the actual constellation that they were originally named for. Those associations weren’t just made up by tropical astrologers; they come to us from the ancient world, when astrology was deeply connected to the events of the actual sky.
In sidereal astrology, seasons also happen – it’s just that they have nothing to do with the zodiac. There is nothing more inherently “springtime” about any constellation; it’s just the cluster of stars that the Sun passes through on the spring equinox. The seasons are related to the Earth’s rotation, and the zodiac is related to the Sun’s path along the ecliptic. They aren’t astronomically yoked together as tropical astrology has us commonly believing.
In the coming Age of Aquarius, will Aquarius suddenly be more “spring”? No, unless people decide to make it so. Again, the “springtime” association with Aries is only due to the fact that the Sun did pass along the Aries constellation in the spring during the Age of Aries, so a lot of lore and mythology arose to describe this phenomena. But then the earth wobbled and the equinox moved.
No sign is inherently related to any one season. The equinox being in a given sign is a marker of a particular age, a moment in cosmological time. The sign on the spring equinox gathers “spring vibes” as befits that particular era, as the sign on the equinox “rules” the era and marks the start of each year. But like everything else in the sky, it all moves.
Astrology is, if nothing else, a way of using the stars and solar system to mark events in time and space. And the specificity and dynamic nature of how much changes is exactly why it is so valuable. This is why we need both systems, the equatorial and the ecliptic, in any approach to astrology. If you encounter an astrology that only uses one of these – and even at that, only the symbolic version of it – then yes, you definitely would be understood for rejecting astrology as “too general” or coming away with the idea that Sun signs are all there is to it. But we hope this post has demonstrated why it would be overzealous to throw all of astrology away based on the shallow end of the pop astrology pool. There is a deeper ocean of resonance that can, in fact, be grounded in observable astronomical and/or symbolic phenomena. And the scientific side of the street is no less poetic and no less beautiful, and in fact can be quite profound.
To learn more about the history of astrology and have a look at some of the other false arguments that tend to come up around the topic of tropical vs. sidereal, see our first two posts in this series, The False Division of Tropical & Sidereal Astrology, Pt. 1, The False Division of Tropical & Sidereal Astrology, Pt. 2, or any of the fantastic references below.
References:
- Bowser, Kenneth. An Introduction to Western Sidereal Astrology. American Federation of Astrologers. 2021.
- Bowser, “Cyril Fagan: The Sidereal Zodiac and the Astrological Ages, April 1969, https://www.westernsiderealastrology.com/fagan-april-1969
- Illustration of the ecliptic and the celestial poles, from http://www.astro.com/astrowiki/en/Ecliptic.
- Crystal Wind (website). “The Basics: The Ecliptic and Sidereal Astrology.” https://www.crystalwind.ca/astrology/astro-types/astrology-basics/the-ecliptic-and-sidereal-astrology.
- Rafferty, John. “Why Does the Tropic of Cancer’s Location on Earth Move Over Time?” Brittanica.com. https://www.britannica.com/story/why-does-the-tropic-of-cancers-location-on-earth-move-over-time. Accessed November 25, 2025.
- https://www.thoughtco.com/tropic-of-cancer-tropic-of-capricorn-3976951
